Refers to a person or shop selling patent medicines or over-the-counter drugs, not necessarily a modern licensed pharmacist. The term is somewhat dated; modern usage often prefers 薬剤師 for a pharmacist or ドラッグストア for a drugstore.
See also: 売薬
Long ago, there was only one druggist in the village.
Compound of 売薬 (patent medicine) and 商 (merchant, trade). The exact historical derivation is uncertain, but the term reflects the traditional trade of selling ready-made medicines.